1. Field of the Invention
The invention relates to a gas spring with end position damping.
2. Description of the Related Art
Such a gas spring is used in particular in doors or tailgates of a motor vehicle and has end position damping at the end of both the push-in stroke and the push-out stroke. The spring prevents violent striking in the end position of the door, for example, and its subsequent bouncing.
Extending over the displacement path are one or more grooves of constant cross section which have a groove runout with decreasing cross section at their two ends. During a movement in the push-out direction of the piston rod, only the region under which flow can occur at the radially inner annular surface of the sealing ring is available for a flow of pressurized gas from a second working chamber into a first working chamber. The consequence of this small throughflow cross section is that the push-out speed of the piston rod is low to begin with and requires high acceleration forces.
A need, therefore, exists for a gas spring which is of simple construction and can be moved with low acceleration forces in both the push-out direction and the push-in direction and also dampens in both end position regions.